“I’m not going to lie: It was hard,” Butler said. “I just had to put it behind me. It was a new week. A new day.”

A new result.

The Chargers cornerback made a critical play late in the fourth quarter Sunday, forcing a fumble near the goal line to stymie a potential Cowboys score. The timely turnover helped seal a run of 20 unanswered points as San Diego overcame injuries to outlast the Cowboys 30-21.

It was a spark the defense needed to shut the door.

The unit forced only two turnovers the first three games. One came on the first defensive play of the season, a tipped pass nose tackle Cam Thomas intercepted. The second came Week 2 during the Eagles’ lateral fest in final-play desperation.

Butler lowered his head into rookie Cowboys wide receiver Terrance Williams, who stretched for the end zone at the 1-yard line. The ball was jarred into the end zone, recovered by cornerback Richard Marshall with 2:50 remaining.

Forcing turnovers was an emphasis in the week of preparation, revisited in the defensive player huddle during the game.

That Butler made the play was fitting. This win was all about overcoming adversity.

The Chargers’ offensive line entered the game missing three starters in left tackle King Dunlap (concussion), left guard Chad Rinehart (toe) and right guard Jeromey Clary (clavicle). In the second quarter, it lost right guard Rich Ohrnberger to a groin injury.

In stepped Steve Schilling, with the team this offseason before a late August cut sent him driving all the way home to Chicago. He just signed back on Wednesday.

An impressed Clary stood in the postgame locker room next to Schilling, who was giving a television interview.

“It’s hard enough to come off the street, and then to come off the bench,” Clary said, shaking his head. “It’s incredible.”

The defense finished the game without outside linebacker Dwight Freeney (calf) and cornerback Derek Cox (knee). And yet, aside from a couple plays Cowboys wide receiver Dez Bryant made that few others can make, it kept Dallas off the scoreboard.

The Chargers’ offense played a role in that.

For the third time in four games, it scored a touchdown on its first possession of the second half. Dallas (2-2) had only one drive in the third quarter, and it ended in a punt.

San Diego (2-2) then scored a field goal and touchdown on its ensuing possessions. All three of the Chargers’ drives to start the second half went at least 80 yards and resulted in points.

If one thing was missing Sunday, it was drama.

Each of the first three games saw the decisive score come in the final 15 seconds. That included last week in Nashville when Titans wide receiver Justin Hunter caught a 34-yard touchdown over Butler, who had signed with the Chargers days earlier and was thrust into the game because of injuries.

Butler wasn’t used as a scapegoat for the play — it never should have to come that, was the team’s message.

On Sunday, he cleared his mind.

“That’s the game of football,” Butler said.

“It’s about making plays. When you get your opportunities, you’ve got to make the best of it.”